Humans are too stupid to prevent climate change from radically impacting on our lives over the coming decades. This is the stark conclusion of James Lovelock, the globally respected environmental thinker and independent scientist who developed the Gaia theory.

"I don't think we're yet evolved to the point where we're clever enough to handle a complex a situation as climate change," said Lovelock in his first in-depth interview since the theft of the UEA emails last November. "The inertia of humans is so huge that you can't really do anything meaningful."

One of the main obstructions to meaningful action is "modern democracy", he added. "Even the best democracies agree that when a major war approaches, democracy must be put on hold for the time being. I have a feeling that climate change may be an issue as severe as a war. It may be necessary to put democracy on hold for a while."

Lovelock, 90, believes the world's best hope is to invest in adaptation measures, such as building sea defences around the cities that are most vulnerable to sea-level rises. He thinks only a catastrophic event would now persuade humanity to take the threat of climate change seriously enough, such as the collapse of a giant glacier in Antarctica, such as the Pine Island glacier, which would immediately push up sea level.

Lovelock says the events of the recent months have seen him warming to the efforts of the "good" climate sceptics: "What I like about sceptics is that in good science you need critics that make you think: 'Crumbs, have I made a mistake here?' If you don't have that continuously, you really are up the creek. The good sceptics have done a good service, but some of the mad ones I think have not done anyone any favours. You need sceptics, especially when the science gets very big and monolithic."

Lovelock, who 40 years ago originated the idea that the planet is a giant, self-regulating organism – the so-called Gaia theory – added that he has little sympathy for the climate scientists caught up in the UEA email scandal. He said he had not read the original emails – "I felt reluctant to pry" – but that their reported content had left him feeling "utterly disgusted".

"Fudging the data in any way whatsoever is quite literally a sin against the holy ghost of science," he said. "I'm not religious, but I put it that way because I feel so strongly. It's the one thing you do not ever do. You've got to have standards."

In his first major interview since the climate-change emails scandal, James Lovelock says he is disgusted by the actions of some scientists, applauds 'good' climate sceptics, and warns that global warming could even lead to war